Unveiling the Mechanism of Nitrogen Fixation by Single-Atom Catalysts and Dual-Atom Catalysts Anchored on Defective Boron Nitride Nanotubes

Itis challenging to explore stable and high-efficiency electrocatalyststoward nitrogen reduction reaction (NRR) under ambient conditions.Herein, the catalytic potential of boron nitride nanotubes (BNNTs)embedded with transition-metal (TM) atoms as electrocatalysts forNRR has been systematically studied by the first-principles calculationmethod. Three single-atom catalysts (SACs), Fe/BNNT, Mn/BNNT, andPd/BNNT, were selected out from 13 candidate materials TM/BNNT (TM= Fe, Co, Ni, Cu, Zn, Ti, V, Cr, Mn, Mo, Pt, Pd, and Au) by densityfunctional theory (DFT) calculations, and their limiting potentialswere -0.65, -0.61, and -0.91 V, respectively.It indicated that they have good catalytic activity for the reductionof N-2 to NH3. Meanwhile, to further improvethe catalytic activity, two dual-atom catalysts (DACs), FeFe/BNNTand MnMn/BNNT, were constructed, their limiting potentials were -0.17and -0.58 V, respectively. The results show that FeFe/BNNTand MnMn/BNNT can greatly improve the catalytic performance. Our workprovides a new idea for constructing high-efficiency electrocatalystswith BNNT as a new carrier.

Automated summary

In this study, the catalytic potential of boron nitride nanotubes (BNNTs) embedded with transition-metal (TM) atoms as electrocatalysts for nitrogen reduction reaction (NRR) was systematically explored. Three single-atom catalysts (SACs) and two dual-atom catalysts (DACs) were selected through density functional theory (DFT) calculations. The results showed that Fe/BNNT, Mn/BNNT, and Pd/BNNT have good catalytic activity for N-2 reduction to NH3, and FeFe/BNNT and MnMn/BNNT can significantly improve the catalytic performance. This work provides a new idea for constructing high-efficiency electrocatalysts with BNNT as a new carrier.